Alkoxysilane containing polyurethane adhesive compositions containing calcium carbonate

Abstract

A composition comprising; (A.) one or more isocyanate functional prepolymers having alkoxysilane moieties; (B) a catalytic amount of one or mote compounds that catalyze the reaction of isocyanate moieties with moieties containing active hydrogen atoms; (C) carbon black; and (D) untreated calcium carbonate in an amount of about 1 to about 30 parts by weight based on the total weight of the composition.

What is claimed is: 
     
       1. A composition comprising:
 (A) one or more isocyanate functional prepolymers having alkoxysilane moieties wherein the isocyanate content of the prepolymers is about 0.1 to about 10 percent by weight of the prepolymers and the alkoxy silane content of the prepolymers is from about 0.2 to about 3.0 percent by weight of the prepolymers and greater than 85 percent by weight of the isocyanate functional prepolymers present contain alkoxysilane moieties; 
 (B) a catalytic amount of one or more compounds that catalyze the reaction of isocyanate moieties with moieties containing active hydrogen atoms; 
 (C) carbon black in an amount of from about 15 to about 35 percent by weight of carbon black based on the total weight of the composition; 
 (D) untreated calcium carbonate in an amount of about 5 to about 15 percent by weight based on the total weight of the composition having an average particle size of about 15 microns or less; and 
 (E) one or more polyfunctional isocyanates. 
 
     
     
       2. The composition according to  claim 1  wherein the catalyst is one or more tertiary amine, one or mare organometallic compounds or a mixture thereof. 
     
     
       3. The composition according to  claim 1  wherein substantially all of the isocyanate functional prepolymers present contain alkoxysilane moieties. 
     
     
       4. The composition according to  claim 1  wherein the calcium carbonate has an average particle size of about 10 microns or less. 
     
     
       5. The composition according to  claim 1  wherein the calcium carbonate has an average particle size of about 7 microns or less. 
     
     
       6. The composition according to  claim 1  wherein an organophosphite is absent from the composition. 
     
     
       7. The composition according to  claim 1  wherein stabilizers are absent from the composition. 
     
     
       8. The composition according to  claim 1  wherein the composition after cure for 7 days at 23° C. plus or minus 2° C. exhibits a tensile strength of 5 MPa or greater and a quick knife adhesion failure mode after 6 days in 90° C. boiling water of 100 percent cohesive failure. 
     
     
       9. The composition according to  claim 1  wherein: the calcium carbonate is present in an amount of about 5 to about 15 percent by weight; and, carbon black is present in an amount of greater than 20 to about 30 percent by weight. 
     
     
       10. The composition according to  claim 1  wherein: the one or more polyfunctional isocyanates are present in an amount of about 1 to about 10 percent by weight. 
     
     
       11. The composition according to  claim 1  wherein the composition includes a hydrophilic material that draws moisture into the composition. 
     
     
       12. The composition according to  claim 1  wherein the hydrophilic material is present in an amount of about 0.1 to about 1.0 percent by weight.